Digital control of electronic ballasts using AC power lines as a communication medium
US7391168B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 13, 2006 |
| Grant date | Jun 24, 2008 |
| Priority date | — |
| Expiry date | Jan 13, 2026 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY04S40/121
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A system for establishing communications between a central lighting controller and a series of electronic dimming ballasts uses an AC power supply line as a communication medium. A MOSFET switched by a control circuit selectively shorts the AC power lines when a rectified version of the power line signal indicates that the power line signal is nearing a zero crossing to create notches in the AC power signal. A simple receiver in each of the ballasts detects the presence or absence of notches in the power signal and interprets the results as digital data indicating a desired dimming level for each of the ballast. The ballasts then adjust their light output accordingly.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.